The effect of Trichoderma asperellum with reduced rates of inorganic fertilizer for growth and yield of carrot

This study was aimed to use Sri Lankan isolate Trichoderma asperellum in combination with reduced rates of chemical fertilizers to evaluate their efficiency as biofertilizer for the growth and yield characters of carrot. Inorganic phosphate sources like Eppawala rock Phosphate (ERP), Tri Calcium Phosphate (Ca3(PO4)2), Ferric Phosphate (FePO4) and Aluminum phosphate (AlPO4) solubilizing capacity of the isolate was estimated by using qualitative and quantitative methods. The pot experiment was carried out in Completely Randomized Design (CRD), consisting of six treatments and four replications. The Treatments were namely T1 (No Fertilizer), T2 (100% NPK - DOA Recommendation), T3 (50% P + N + K), T4 (50% P + Trichoderma asperellum + N + K), T5 (75% P + N +K) and T6 (75% P + Trichoderma asperellum + N + K). The results of qualitative estimation of Trichoderma asperellum exhibit good mycelial growth in the inorganic phosphate enriched media while the quantitative estimation results showed the variable potential of the Trichoderma asperellum to solubilize inorganic phosphates. According to the results of the pot experiment, significantly (P < 0.05) better results of growth and yield parameters were observed from treatments T6, T4 and T2. The results of the present study reveals that Sri Lankan isolate Trichoderma asperellum can be a growth and yield promoter and can be used as a biofertilizer to reduce the usage of costly and environmentally toxic inorganic fertilizer.